NFL Point spread: arbitrage calculator
- Market
- 2-way
- Typical overround
- 4%–5%
- Sample arbitrage return
- -3.51%
- Profit on every outcome
- -3.51
- Total stake
- 100.00
- Sum of implied probabilities
- 103.64%
| Leg | Odds used | Effective odds | Stake |
|---|---|---|---|
| Back Favorite -3.5 | 1.950 | 1.950 | 49.48 |
| Back Underdog +3.5 | 1.910 | 1.910 | 50.52 |
| If this wins | Legs that pay | Gross return | Commission | Net profit |
|---|---|---|---|---|
| Favorite -3.5 | Favorite -3.5 | 96.49 | 0.00 | -3.51 |
| Underdog +3.5 | Underdog +3.5 | 96.49 | 0.00 | -3.51 |
No arbitrage: -3.51% return
The point spread is priced at -110 on each side at most books, with the line rather than the price moving to balance action. Whole-number lines can push, which refunds the stake and breaks an arbitrage.
Market structure
NFL Point spread has 2 outcomes (
Favorite -3.5, Underdog +3.5). Bookmakers typically price it with an overround between 4% and
5%. For an arbitrage you need prices from at least two books whose implied probabilities, taken at the best price per outcome, add up to less than 100%.
Worked example
Two books quote 1.91 / 1.91 and 1.95 / 1.87. Taking the best price for each outcome (1.95 / 1.91) gives an implied sum of 103.64%. Arbitrage: no, return -3.51%. The calculator above is pre-filled with those best prices; the stakes for 100 in total are 49.48 / 50.52.
| Outcome | Book A | Book B | Best | Stake of 100 |
|---|---|---|---|---|
| Favorite -3.5 | 1.91 | 1.95 | 1.95 | 49.48 |
| Underdog +3.5 | 1.91 | 1.87 | 1.91 | 50.52 |
Two-way specifics
Point spreads carry a push risk: if the line is a whole number and the game lands on it, one leg is refunded and the position is no longer an arbitrage. Prefer half-point lines or check both books use the same number.
Frequently asked questions
How many legs does a NFL Point spread arbitrage need?
One per outcome: 2 legs covering Favorite -3.5, Underdog +3.5. Every outcome must be backed for the position to profit whatever happens.
How large is the overround in NFL Point spread?
Typically 4% to 5% at a single book. An arbitrage needs the best prices across books to sum below 100%, so the gap between books has to exceed the margin.
Is the worked example on this page a real arbitrage?
The sample prices give an implied sum of 103.64% at the best price per outcome (arbitrage: no). They are illustrative; live prices change constantly.
What can go wrong with an arbitrage across 2 outcomes?
A leg not being available at the assumed price, a void or push on one leg, different settlement rules between books, and stake limits that stop you placing the full amount.